Split inputs into a separate class (descending from Effect) instead of handling them...

[movit] / input.cpp

diff --git a/input.cpp b/input.cpp
new file mode 100644 (file)
index 0000000..1e460f0
--- /dev/null
+++ b/input.cpp
@@ -0,0 +1,108 @@
+#define GL_GLEXT_PROTOTYPES 1
+
+#include <string.h>
+#include <GL/gl.h>
+#include <GL/glext.h>
+#include <assert.h>
+
+#include "input.h"
+#include "util.h"
+
+Input::Input(ImageFormat image_format, unsigned width, unsigned height)
+       : image_format(image_format),
+         needs_update(false),
+         use_srgb_texture_format(false),
+         needs_mipmaps(false),
+         width(width),
+         height(height)
+{
+       register_int("use_srgb_texture_format", &use_srgb_texture_format);
+       register_int("needs_mipmaps", &needs_mipmaps);
+}
+
+void Input::finalize()
+{
+       // Translate the input format to OpenGL's enums.
+       GLenum internal_format;
+       if (use_srgb_texture_format) {
+               internal_format = GL_SRGB8;
+       } else {
+               internal_format = GL_RGBA8;
+       }
+       if (image_format.pixel_format == FORMAT_RGB) {
+               format = GL_RGB;
+               bytes_per_pixel = 3;
+       } else if (image_format.pixel_format == FORMAT_RGBA) {
+               format = GL_RGBA;
+               bytes_per_pixel = 4;
+       } else if (image_format.pixel_format == FORMAT_BGR) {
+               format = GL_BGR;
+               bytes_per_pixel = 3;
+       } else if (image_format.pixel_format == FORMAT_BGRA) {
+               format = GL_BGRA;
+               bytes_per_pixel = 4;
+       } else {
+               assert(false);
+       }
+
+       // Create PBO to hold the texture holding the input image, and then the texture itself.
+       glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 2);
+       check_error();
+       glBufferData(GL_PIXEL_UNPACK_BUFFER_ARB, width * height * bytes_per_pixel, NULL, GL_STREAM_DRAW);
+       check_error();
+       glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
+       check_error();
+       
+       glGenTextures(1, &texture_num);
+       check_error();
+       glBindTexture(GL_TEXTURE_2D, texture_num);
+       check_error();
+       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+       check_error();
+       // Intel/Mesa seems to have a broken glGenerateMipmap() for non-FBO textures, so do it here
+       // instead of calling glGenerateMipmap().
+       glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, needs_mipmaps);
+       check_error();
+       glTexImage2D(GL_TEXTURE_2D, 0, internal_format, width, height, 0, format, GL_UNSIGNED_BYTE, NULL);
+       check_error();
+
+       needs_update = false;
+}
+       
+void Input::set_gl_state(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num)
+{
+       if (needs_update) {
+               // Copy the pixel data into the PBO.
+               glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 2);
+               check_error();
+               void *mapped_pbo = glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, GL_WRITE_ONLY);
+               memcpy(mapped_pbo, pixel_data, width * height * bytes_per_pixel);
+               glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB);
+               check_error();
+
+               // Re-upload the texture from the PBO.
+               glActiveTexture(GL_TEXTURE0);
+               check_error();
+               glBindTexture(GL_TEXTURE_2D, texture_num);
+               check_error();
+               glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));
+               check_error();
+               glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+               check_error();
+               glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+               check_error();
+               glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
+               check_error();
+
+               needs_update = false;
+       }
+
+       // Bind it to a sampler.
+       set_uniform_int(glsl_program_num, prefix, "tex", *sampler_num);
+       ++*sampler_num;
+}
+
+std::string Input::output_fragment_shader()
+{
+       return read_file("input.frag");
+}